Drill



' H. BERNAY.

DRILL.

APPLICATION FILED FEB. 24. 1919.

1,359,318, I Patented Nov. 16,1920

.IIIJH 2 u I mm; 2. A /l'-' mmi m//// I Inventin- By M Atty.

- HENRI TBERNAY, OF SAN FRANCISCO,

UNITED STATES PATENT OFFICE.

' Application filed February 24, 1919.

To all whom it may concern. I

Be it known that I, HENRI BERNAY, a citizen p fthe United States,residing in the city and county of San Francisco, State of California,have invented anew and useful Improvement in Drills, ing is aspecification.

y invention relates to improvements in rock drills and the like whereina slotted stock operates in conjunction with a pin to maintain a contactbetween the inner ends of the bits and SlOEE.

The primary object of thepresent invention is to provide an improveddrill having detachable bits; r

A further object of the present invention is to provide an improveddrill of the character described having improved means for removablysecuring bits to said drill;

A still further object of the present invention is to seat detachablebits within slots in the stock in such a manner that no shearing strainwill be'applied to the bit securing means; r

It is also an object of thepresent invention to provide an improved formof a bit for operation in connection with the stock of the drill, saidbit having a reduced inner end to provide an enlarged outer end adaptedto increase the cutting portion of the bit; '1

It is still further desired to'provide an improved bit of the typedescribed wherein the slots are formed to resist slitting and to preventa lateral movement of the bit.

I accomplish these several objects by means of the improved devicedisclosed in the drawings forming a part of the present specificationwherein like characters of reference are used to designate similar partsthroughout the said specifications and drawings, and in which- F igure 1is a fron elevation of my improved drill;

Fig. 2 is a vertical sectional view of the drill Fig. 3 is a sideelevation of Fig. 1;

Fig. 1" is a bottom plan view of Fig. 1;

Fig. 5 is an elevation of one of the bits removed from the stock;

ig. 6 is a vertical sectional view of the lower portion of a stock takenon line 66 of Fig. 1 in the direction indicated; and Fig. 7 is adetailed view of the retaining P CALIFORNIA, 'ASSIGNOR, BY MEYSNE ,mnms, T0 FRED w. THURSTON, or SAN FRANCISCO, CALIFORNIA.

of which the follow- ASSIGNE- DRILL.

Patented Nov. 16, 1920. Serial No. 279,002.

Referring to the drawings the numeral 1 is used slots 2 which passthrough a of said stock The bore 3 is rovided with an enlarged taperingportion 4 within which is seated the tapered portion 6 of a secondstock. 7 hav- 111" a central bore 8 communicating with the central bore3 of the stock 1. he inner ends of the slots 2 of the stock 1 areprovided at their corners and throughout the length thereof With arcuategrooves 9, t e purpose of which will hereinafter be more fully setforth.

rcuate bits 11 are seated within the slots 2 and are provided with onecutting edge 12 which" follows the curvature of the body, sald bits- 11being shaped to fit within the slots 2, the side walls of which areparallel with each other and sea upon those portions of the inner endsof the grooves 9 therein so that when a pressure is applied to thecutting edges 12 of the bits swage or mushroom said portion into theventing thesplitting of the stock 1 The bits 11 as at 14 to provide awider cutting edge 12 and also to facilitate in reaming the hole beingdrilled, said reaming function being carried out by the ends of the bitadjacent the cutting edge 12.

Jach-bit 11 is rovided with a transverse centrally disposed elongatedretaining aperture 16 the inner ends only of said apertures 16registering with a transverse channel 18 passing through the stock 1 andthe slots 2 and between the inner and outer ends of said slots 2. I

' transverse pin 19 is removably mounted within the channel 18 and theretaining'or locking apertures 16, said pin 19 thereby engaging theinner ends only of the elongatedapertures 16 whereby a' pressureappliedto the cutting edges 12 of the bits 11 will be prevented from shearingthe pin longitudinally.

The distance from the inner ends of the apertures 16 to the inner endsof the bits 11 channel 18 whereby the said inner ends of the bits 11 arefirmly seated upon the anvils or portions of the inner ends offihe Wlllbetransmitted to said said grooves 9-thereby preare reduced at theirinner ends endas at 23 so as to frietionally engage the 'the oppositeedge of said body, vided with a centrally disposed locking walls of thechannel 18 and thereby prevent inadvertent removal of the retaining pin19.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is- 1. A drill comprising a stock having slotsin one end thereof the side walls of the slots being parallel with eachother; bits removably mounted within the slots and provided withtransversely disposed apertures; means detachably mounted within thestock for engaging only the inner ends of the apertures to hold theinner ends of said bits against the inner ends of the slots; and meansfor preventing a transverse movement of the bits relatively to the stockto prevent a shearing strain on the aperture engaging means.

2. A'drill comprising a stock having slots therein and grooves extendingthroughoutthe length and the bottom of each slot and at the cornersthereof; bits removably mounted within the slots and having their innerends seated upon those portions of the inner ends of the slots betweenthe grooves; and means for retaining the bits in such position. I

3. A drill comprising a stock having arcuate slots therein and groovesextending throughout the length of the slots and at the corners thereof;arcuate bits removably mounted within the slots and having their innerends seated upon those portions of the inner ends of the slots betweenthe grooves; and a transverse pin mounted within the stock and bits toretain said bits in such position.

4. A bit, arcuate in outline, having a cutting edge following thecurvature of the body, said. cutting edge being longer than andproaperture.

5. A bit, arcuate in outline, having a cut- -slots in one endcthereofting edge following the curvature of the body, said cutting edge beinglonger than theopposite edge 'of the bit, and provided with anelongated, centrally disposed locking aperture.

6. A bi having a cutting edge on one side thereof longer thanthelengthof the opposite edge, and provided with a transverse centrally disposedlocking aperture, and a rib on one face thereof to prevent lateralmovement of said bit when mounted within a suitable stock.

7. A bit, arcuate in outline, having a cutting edge following thecurvature of the body, said cutting edge being longer than the oppositeedge, and having a transverse centrally -disposed locking aperture and arib on one face thereof to prevent lateral movement of, the bit whenmounted within a suitable stock.

8. A bit, arcuate in outline, having a cutting edge longer than the edgeopposite, and provided witha rib formed on the concaved face thereof toprevent lateral movement of the bit when in a suitable stock andlikewise provided with a transverse centrally disposed locking aperture.

9. A drill'eomprising a stock having slots in one end thereof; bitsremovably mounted within the slots and provided with transversecentrally disposed locking apertures;

and a split pin removably mounted within the stock and engaging only theinner surfaces of the bit apertures to retain said bits within theslots.

10'. A drill comprising a stock having slots in one end thereof andlongitudinal grooves formed in the outer walls of each slot; bitsremovably mounted within the slots and provided with longitudinal ribsadapted to engage the; grooves in the walls of the slots so as toprevent lateral movement of said bits within the slots.

11. A drill comprising a stock having and longitudinal grooves formed inthe outer walls of each slot; bits removably mounted within the slotsand provided with longitudinal ribs adapted to engage the grooves in thewalls of the slots so as to prevent lateral movement of said bits withinthe slots; and means for preventing a longitudinal movement of the bitswithin the slots.

In witness whereof I signature.

BERNAY.

hereunto set my

